package com.itheima.ai.repository;

import org.springframework.stereotype.Component;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@Component
public class InMemoryChatHistoryRepository implements ChatHistoryRepository {

    private final Map<String, List<String>> chatHistory = new HashMap<>();

    @Override
    public void save(String type, String chatId) {
//        if (!chatHistory.containsKey(type)) {
//            chatHistory.put(type, new ArrayList<>());
//        }
//        List<String> chatIds = chatHistory.get(type);
        //简化成下面的新写法
        List<String> chatIds =chatHistory.computeIfAbsent(type, k -> new ArrayList<>());
        if (chatIds.contains(chatId)) {
            return;
        }
        chatIds.add(chatId);
    }

    @Override
    public List<String> getChatIds(String type) {
//        List<String> chatIds= chatHistory.get(type);
//        return chatIds == null ?new ArrayList<>(): chatIds;
        //可以简化成下面，意思是：取type,取到就返回，取不到就new ArrayList<>()
        return chatHistory.getOrDefault(type,new ArrayList<>());
    }
}
